Advanceable roof support suitable for use in mines



P. FARR Jan. 23, 1968 ADVANCEABLE ROOF SUPPORT SUITABLE FOR USE IN MINES2 Sheets-Sheet 1 Filed March 29, 1965 IMVEMTOQ VErE/e FAKK whm ATToamavJan. 23, .1968

Filed March 29, 1965 P. FARR 3,364,683

ADVANCEABLE ROOF SUPPORT SUITABLE FOR USE IN MINES 2 Sheets-Sheet 2INVEM'TOE Para F'AEK ATToewzy United States Patent 3,364,683 ADVANCEABLEROOF SUPPORT SUITABLE FOR USE IN MENES Peter Farr, Cheltenham, England,assignor to Dowty Mining Equipment Limited, Ashchurch, Tewi-xesbury,Engiand, a British company Filed Mar. 29, 1965, Ser. I o. 443,421 Claimspriority, application Great Britain, Miar. 31, B64, 13,1'77/64 11Claims. (Cl. 61-45) ABSTRACT OF THE DISCLOSURE During advance ofindividual roof supports, such as are pivotally connected to theconveyor, such a roof support tends to slew about its pivotalconnection. For proper support of the roof and coordination of thesuccessive roof supports any such tendency to slew about should becounteracted, and the roof supports when reset in their ultimateadvanced positions should be left in parallelism to one another, eachperpendicular to the working face of the mine and to the ultimateadvanced position of the conveyor.

Various attempts have been made to guide the roof supports as theyadvance so that they do not slew about, but this is likely to set upbinding in the guide means, of such nature as to prevent proper advance,and to require corrective measures that are rather dangerous to miners.There have been other attempts to permit slewing, followed byrealignment by interengagement between an advancing roof support and oneor more temporarily fixedly positioned roof supports.

According to the present invention each individual roof supportincorporates means that reacts between the same and a part of its ownadvancing means to effect realignment automatically, within each givenroof support, as its advance proceeds. This is achieved by utilizingspaced abutments on one part of the jack that efiects advance, thatcooperate with complemental abutments carried by the floor-engagingmember but which are spaced somewhat farther apart (in the direction ofadvance) than the first-mentioned abutments, whereby some slightrelative shifting axially of the one part of the jack with respect tothe floor support is effected. Thereby slewing of the jack about thepivotal connection of its other part to the conveyor is permitted; theabutments are so mounted as to be free to move vertically to accommodateroughness of the floor, but not horizontally. Slewing is also producedby a couple that develops during advance by reason of the location ofthe pivotal 0onnec tion of the jack to the conveyor at a point off-setfrom the thrust axis of the jack. At the same time that tendency to slewabout is counteracted and reduced, and the roof support is restored toits correct disposition, by reaction between a profiled surface of oneof the abutments and its complemental abutment.

Detailed description This invention relates to mining equipment,especially such as includes advanceable roof support assemblies andalternatively advanceable snakeable conveyors that serve as anchorages.

Embodiments of the present invention will now be described, by way ofexample, with reference to the accompanying drawings of which,

FIGURE 1 is a plan view of a roof support assembly secured to aconveyor,

FIGURE 2 is a side view of a part of the roof support assembly of FIGURE1,

FIGURE 3 is a plan view of part of a floor beam of 'ice a modified roofsupport assembly (with a steering arm omitted),

FIGURE 4 is a sectional view of the floor beam along the line 4-4 ofFIGURE 3,

FIGURE 5 is a plan view of the steering arm for use with the floor beamshown in FIGURE 3, and

FIGURE 6 is a side view of the steering arm shown in FIGURE 5.

With reference to the accompanying drawings, FIG- URES 1 and 2 show amine roof support assembly including an advanceable roof support 1 towhich is secured a iiuid-pressure-operated piston-and-cylinder jack 2.The roof support 1 includes two spaced-apart floor beams 3, 4 which areparallel to one another and to the direction in which the roof supportadvances. The floor beams 3, 4 are rigidly connected by connecting means5. The floor beam 3 carries three fluid-pressure-operated props 6, onebehind the other, and the floor beam 4 carries twofluidpressure-operated props 7, one behind the other. The rear ends ofthe floor beams 3, 4 are laterally aligned, but the floor beam 3 islonger than the floor beam 4. The front prop 7 is laterally aligned withthe rear prop 6. The front prop 6 is carried by a portion of the floorbeam 3 which projects beyond the floor beam Each prop 6, 7 is mounted ina resilient prop mounting 3 carried by the respective floor beam 3, 4such that each prop 6, 7 is resiliently urged to a predetermined angularposition relative to the respective floor beam 3, 4 and is capable of alimited amount of angular movement from its predetermined angularposition. The prop mounting 8 has not been shown in detail, as suchmountings are well-known.

The middle and rear props 6 and the two props 7 carry a roof canopy 9 insuch a manner that they are capable of a limited amount of angularmovement relative to the canopy 9. The front prop 6 carries a roof bearn11 connected to the canopy 9 by a hinge 12 such that the roof beam 11and canopy 9 are capable of relative angular movement about an axisextending laterally of the direction of advance. The front prop 6 iscapable of a limited amount of angular movement relative to the roofbeam 11.

A roof support with two floor beams rigidly connected together byconnecting means is the subject of US. patent application of T. D. H.Andrews, Ser. No. 430,922, filed Feb. 8, 1965.

The cylinder 13 of the jack 2 has a spigot 14 at its rear end which islocated in a slot formed by two upstanding lugs 15 secured to theconnecting means 5. This enables the jack 2 to move angularly relativeto the roof support by a limited amount about a vertical axis and tomove by a limited amount vertically and also horizontally relative tothe roof support.

A steering arm 16 is carried by the floor beam 3 at a position justbehind the front prop 6. The steering arm 16 extends towards the floorbeam 4 across and above the front end portion of the jack cylinder 13.This front end portion of the jack cylinder 13 has two blocks 17 securedthereto, one one each side of the centre line of the cylinder 13, thepurpose of which is to provide flat surfaces on which the steering arm16 rests. Also, two upstanding lugs 18 are secured to the cylinder 13 atpositions spaced in a manner to be described from the lugs 15, and thetwo lugs 18 carry a retainer 19 which extends forwardly over the blocks17 and over the steering arm 16, to prevent that arm rising from theposition where lugs 18 can contact it.

The forwardly-facing surfaces of the lugs 18 and the rearwardly-facingsurface of the steering arm 16 are shaped for a purpose which will bedescribed later. An end portion of the steering arm 16 is located in aslot 21 in the floor beam 3 and has a projection 22 which is located ina further slot 23 communicating with the slot 21. The steering arm 16 isthereby capable of angular movement about an axis passing through theprojection 22 and of vertical movement in the slots 21, 23. The oppositeend portion of the steering arm 16 has a stop 24- which limits angularmovement of the jack 2 relative to the roof support 1.

The piston rod of the jack 2 has an offset portion 26 at its free end,and this offset portion 26 is pivotally attached to a conveyor 27 by apin 28, the axis whereof is upright.

In FIGURES 1 and 2, the jack 2 is in its fully contracted condition andthe roof support 1 is in a fully-advanced position relative to theconveyor 27. FIGURE 1 shows the initial position of the jack 2' when thejack 2 has been supplied with fiuid under pressure in a jack-extendingsense to advance the conveyor 27, the roof support 1 being in aroof-supporting condition with all its props 6, 7 set. The jack cylinder13- has moved rearwardly with the rear end of the jack cylinder 13abutting the lugs 15. The lugs 18 at this time are spaced from thesteering arm 16-. Thus, as the conveyor 27 then advances, the jack 2reacts against the lugs 15, pushes at the pin 28, and can move angularlyby an amount predetermined by the shape of the lugs 15.

When the conveyor 27 has been advanced, the props 6, 7 are released sothat the canopy 9 and roof beam 11 are lowered from the roof, and fluidunder pressure is then supplied to the jack 2 in a jack-contractingsense. Initially, the jack cylinder 13 moves forwardly until the frontsurfaces of the lugs 18 abut the rear surface of the steering arm 16,the rear end of the cylinder 13 then being spaced from the lugs 15. Thejack-contracting force is then transmitted through the steering arm 16to the roof support 1 with the result that the roof support 1 advancestowards the conveyor 2 Owing to the presence of the offset portion 26secured to the piston rod 25, the line of action of the force exerted bythe jack 2 does not pass through the pin 28, and the resultant coupletends to balance the couple caused because the centre of frictionbetween the roof support 1 and the floor is displaced from the line ofaction of the force exerted by the jack in the direction of the fioorbeam 3.

If the roof support 1 does tend to slew about the intended direction ofadvance parallel to the line of action of the jack 2, the relativemovement between the shaped front surfaces of the lugs 18 and the shapedrear surface of the steering arm 16 causes the advancing force exertedby the jack 2 through the steering arm 16 on the roof support 1 to havea component tending to correct the slewing movement. Such slewing may becaused, for example, by unevenness in the floor. When such unevenness isencountered, the steering arm 16 can move angularly and vertically inthe slots 21, 23, as previously described.

FIGURES 3 to 6 show a modified steering arm 31 and door beam 32. An endportion 33 of the steering arm 31 fits into a slot 34 in the floor beam32 and has a projection 35 which fits into a further slot 36communicating with the slot 34. The rear portion 38 of the slot 34 hasless depth than the remainder of the slot 34. The arrangement is suchthat upward angular movement of the steering arm 31 about projection 35by more than a predetermined amount causes the projection 35 to moveupwardly out of the slot 36, with the result that the steering arm 31becomes disconnected from the floor beam 32. Such upward angularmovement of the steering arm 31 may occur with an exceptionally unevenfloor, and the disconnection of the steering arm 31 from the floor beam32 prevents damage to the jack and steering arm 31.

The conveyor 27 may have parts which, during the last part of theadvance of the roof support, override the operation of the steering arm16 and align the roof support 1 in a desired manner with the conveyor27. When the roof support 1 has been reset against the roof after itsadvance, the roof support and the parts of the conveyor 27 mayco-operate to prevent movement of the conveyor 27 in a directionperpendicular to the direction of advance.

What I claim is:

1. Mining equipment including, in combination, an advanceable anchorageand an advanceable roof support, said roof support having afloor-engaging member and at least one telescopic prop carried by thefloor-engaging member, a telescopic jack including a first and acomplemental second part, for advancing each of the floorengagingmembers and the anchorage by reaction of one to the other, said firstpart of said jack being pivotally connected to said anchorage, and hencecapable of slewing laterally with respect to the direction of advance,and the second part being connected to said floor-engaging member, oneend portion of said second part being remote from the anchorage, saidremote end portion and an adjacent part of the floor-engaging memberhaving complemental abutments, and the opposite end portion of thesecond part, that nearer the anchorage, and an adjacent part of thefloor-engaging member, also having complemental abutments, the severalabutments being so spaced that when the abutments at one end areabutted, those at the opposite end are spaced apart, and vice versa, oneof the abutments at such nearer end being angularly directed withrespect to its complemental abutment to guide advancing movement of thefloor-engaging member to counteract any lateral slewing of the jack andof the connected floor-engaging member.

2. Mining equipment as in claim 1, wherein the pivotal connection of thefirst part of the jack to the anchorage is offset from the line ofthrust of the jack, and the abutment carried by the floor-engagingmember at such nearer end is bowed concavely with respect to itscomplemental abutment.

3. Mining equipment as in claim 1, wherein props on the floor-engagingmember are arranged in two parallel rows directed in the direction ofadvance, one such row being longer than the other, the jack beingdisposed to the side of the shorter row that corresponds to the longerrow, and the pivotal connection of the jack to the anchorage beingoffset from the jacks line of thrust towards the longer row, theabutment carried by the floor-engaging member at such opposite end beingbowed concavely with respect to the complemental abutment to counteractthe slewing tendency produced by the offset location of the jack and itspivotal connection.

4. Mining equipment as in claim 1, wherein the abutment carried by thefloor-engaging member at such nearer end is the one that is angularlydirected.

5. Mining equipment as in claim 4, wherein the angularly directedabutment is separate from the floorengaging member, and means supportingsaid abutment from said floor-engaging member for freedom of up and downmovement of the abutment relative to the floorengaging member, butrestraining relative horizontal movement.

6. Mining equipment as in claim 5, wherein the means: supporting theangularly directed abutment is arranged for pivotal movement about ahorizontal axis.

7. Mining equipment as in claim 6, wherein the means. supporting theangularly directed abutment is also arranged for its additional bodilyvertical movement.

8. Mining equipment as in claim 7, wherein the angularly directedabutment is carried upon one end of an arm, the floor-engaging memberbeing formed with a transversely directed upright slot wherein the armsopposite end is received for vertical movement, a pivot projection fromsaid opposite end being received in a second upright slot angularlyrelated to the first slot, for pivotal movement.

9. Mining equipment as in claim 8, including means to limit upwardmovement of the slot-confined end of the arm, to effect release of thepivot projection from its second slot in the event of excessive verticalmovement of the arm.

19. fining equipment including in combination, a snakea'ole conveyor, anadvanceable roof support having releasable means settabie between thefloor and the roof, a two-part telescopic jack a first part whereof isconnected at its forward end to said conveyor, its second part having aforward and a rearward bearing surface, said bearing surfaces beingspaced apart lengthwise of the jacks second part by a given distance, aforward and a rearward thrust-receiving surfaces carried by the roofsupport in position to receive thrust from the respective bearingsurfaces, said thrust-receiving surfaces being spaced apart a distancein excess of the spacing of said bearing surfaces, whereby as eitherpair of bearing and thrust-receiving surfaces is engaged, the other pairis disengaged.

11. Mining equipment including in combination, a snakeable conveyor, anadvanceable roof support having releasable means settable between thefloor and the roof, a telescopic fluid-pressure jack the piston whereofis connected at its forward end to said conveyor, forward and rearwardbearing surfaces upon the jack cylinder spaced apart by a givendistance, thrust-receiving surfaces carried by the roof support inposition to receive thrust from the respective bearing surfaces, uponthe jack cylinder that are complementai to each such bearing surface butspaced apart a distance sufiiciently in excess of the spacing betweensaid bearing surfaces that as the complemental rearward surfaces areengaged during advance of the conveyor the complemental forward surfacesare spaced apart, to permit slewing of the roof support, and vice versa,as the forward surfaces are engaged during advance of the roof supportthe rearward surfaces are spaced apart, the forward surfaces beingangularly directed to counteract any slewing by their interengagernent.

References Cited UNETED STATES PATENTS 2,910,281 16/1959 \Vilkenloh etal. 2621 3,113,661 12/1963 Linlze et al. 198-126 FOREIGN PATENTS1,363,750 6/1964 France.

DAVID J. VJILLIAMOVVSKY, Primary Examiner.

